 | In crash events plastic parts are heavily exposed to high rates of stressing and deformation. Extensive knowledge of the mechanical behavior of plastics concerning low rates are available. Due to the complex experimental procedure only a few mechanical properties within crash typical areas (up to 72 km/h) are determined yet. However, to increase safety reliable material properties at crash typical speeds are essential for a precise simulation of crash procedures of plastic parts (e.g. by FEM).
In a high speed tensile test the required high stressing rates of 20 m/s (72 km/h) are reached by means of a servo-hydraulic test equipment. At the same time the occurring local deformations are determined by a ultra high speed camera with a maximum frequency by 1 MHz. This corresponds to the admission of 1 million pictures/second.
The results of the high speed tensile tests are "true stress strain curves", which are necessary data inputs for precise crash simulation programs. As an alternative pure "force displacement curves" can be determined.
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